Camera and shutter device

Abstract

A camera includes a movable aperture stop plate, which changes over a light path of object light between plural stop states. A depressible shutter release button is provided. A shutter mechanism is released in response to depression of the shutter release button after a charging operation and changing over the movable aperture stop plate, to provide an exposure to the photo film. A photometric circuit including a CdS element measures object brightness adapted for changing over the movable aperture stop plate. A photometric switch includes first and second switch segments, is turned on when pressed, to supply the photometric circuit with power. A blocking pin blocks and turns off the first and second switch segments upon completion of the charging operation of the shutter mechanism, and comes away from the photometric switch when the shutter release button is depressed.

What is claimed is:  
     
       1. A camera, including a depressible shutter release button, and a shutter mechanism for being released in response to depression of said shutter release button, to provide an exposure to said photo film, said camera comprising: 
       a photometric circuit for measuring object brightness;  
       an aperture stop mechanism for setting a selected one of plural stop openings according to said object brightness;  
       a photometric switch, including first and second switch segments, for being turned on when pressed, to supply said photometric circuit with power;  
       a first blocking mechanism for holding said second switch segment to prevent contact with said first switch segment upon completion of charging operation of said shutter mechanism, and for setting free said second switch segment by releasing said holding when said shutter release button is depressed; and  
       a shifting mechanism for pressing said second switch segment to contact said first switch segment after said first blocking mechanism releases said holding of said second switch segment.  
     
     
       2. A camera as defined in  claim 1 , further comprising a second blocking mechanism for holding said second switch segment when said shutter mechanism is actuated, to keep said second switch segment from contacting said first switch segment until a start of said charging operation of said shutter mechanism. 
     
     
       3. A camera as defined in  claim 2 , further comprising a delay mechanism for being shifted to a charged position by winding operation of said photo film, and for being shifted to a released position in response to said depression of said shutter release button, to actuate said shutter mechanism; 
       wherein said first blocking mechanism is moved according to shifting of said delay mechanism, holds said second switch segment to prevent contact with said first switch segment when said delay mechanism is in said charged position, and releases said holding of said second switch segment when said delay mechanism is in said released position.  
     
     
       4. A camera as defined in  claim 3 , further comprising a switch gear for rotating according to shifting of said delay mechanism; 
       wherein said first blocking mechanism is a blocking pin, said shifting mechanism is a shifting projection, and said blocking pin and said shifting projection are formed to protrude from said switch gear.  
     
     
       5. A camera as defined in  claim 4 , wherein said first switch segment is offset from a moving path of said blocking pin and said shifting projection, and is free therefrom; 
       said second switch segment has a portion disposed in said moving path, has a springy characteristic, is pushed by said shifting projection while said delay mechanism is shifted between said charged and released positions, and subsequently returns to an original state with resiliency.  
     
     
       6. A camera as defined in  claim 5 , wherein said delay mechanism includes a tooth train portion having plural teeth arranged along an arc; 
       further comprising a transmission gear portion, formed with said switch gear, meshed with said tooth train portion, for rotating.  
     
     
       7. A camera as defined in  claim 6 , wherein said delay mechanism includes a delay lever movable pivotally; 
       said second blocking mechanism is a second blocking pin formed to protrude from said delay lever.  
     
     
       8. A camera as defined in  claim 7 , wherein said switch gear further includes an escapement wheel portion, formed with said transmission gear portion, and having said blocking pin and said shifting projection protruding from a periphery thereof; 
       further comprising a governor mechanism meshed with said escapement wheel portion, for keeping a swing of said delay lever at a regular speed.  
     
     
       9. A camera as defined in  claim 8 , further comprising a transmission lever, being pivotally movable, for changing over said aperture stop mechanism; 
       wherein said switch gear further includes a retention ridge, having a predetermined radius, for retaining said transmission lever when said delay lever is in said charged position, and for coming away from said transmission lever when said delay lever is in said released position to allow changing over said aperture stop mechanism.  
     
     
       10. A camera as defined in  claim 9 , further comprising a retention lever for transmitting shifting of said shutter release button to said delay lever; 
       wherein said delay lever is rotatable between said charged and released positions, and has a retention projection;  
       when said delay lever is in each one of said released and charged positions, said retention projection is retained by said retention lever;  
       while said delay lever rotates toward said released or charged position, said retention projection is released from said retention lever.  
     
     
       11. A camera as defined in  claim 1 , wherein said shutter mechanism includes: 
       a delay lever for moving from a charged position toward a released position in response to said depression of said shutter release button, and for reaching said released position upon lapse of a delay time;  
       a shutter drive lever for moving from a first position toward a second position when said delay lever reaches said released position;  
       a shutter blade, driven by said shutter drive lever moving toward said second position, for opening and shutting a photographic light path;  
       further comprising a friction mechanism for providing braking operation to said delay lever by frictional contact therewith, to set said delay time long.  
     
     
       12. A camera as defined in  claim 11 , further comprising: 
       a flash emitter for applying flash light to a photographic object;  
       a flash circuit board for controlling said flash emitter; and  
       an aperture stop actuator, secured to said flash circuit board, for controlling shifting of said aperture stop mechanism between said plural stop openings.  
     
     
       13. A camera as defined in  claim 12 , wherein said aperture stop mechanism includes: 
       a large stop opening disposed behind a taking lens in a stationary manner; and  
       a movable aperture stop plate, having a small stop opening smaller than said large stop opening, being movable between a large aperture position and a small aperture position, said movable aperture stop plate, when in said large aperture position, being offset from behind said taking lens, and when in said small aperture position, being disposed behind said taking lens to set said small stop opening.  
     
     
       14. A camera as defined in  claim 13 , further comprising: 
       a main body for being loaded with said photo film;  
       an exposure aperture, formed in said main body, for creating an exposed region of a frame in said photo film;  
       a light-shielded tunnel, disposed in connection with a front of said exposure aperture, for covering said photographic light path, said light-shielded tunnel having said shutter mechanism secured thereto, to constitute an exposure unit together therewith; and  
       a lens unit having said aperture stop mechanism, and having said taking lens, disposed in a front thereof, for introducing said object light from said object.